Mona Ghassemi, assistant professor in the Bradley Department of Electrical and Computer Engineering, has received the Department of Energy’s Early Career Research Award to develop a complete plasma model from discharge initiation to flashover to predict electrical breakdown in electrical insulating materials.
Controlled, low-temperature plasmas or nonthermal plasmas in air at atmospheric pressure are of interest for a variety of technologies, including plasma display applications, ozone production, exhaust gas, surface treatments, cancer treatments, and pollution control, Ghassemi said. But a sudden occurrence of such plasmas or discharges in an insulation system is highly undesirable.
Such discharges can lead to an electrical breakdown or flashover, resulting in a complete failure of an electrical device’s insulation system. Problems like these are critical to solve, Ghassemi said, because of the important role insulation systems play within the technologies we use.
“A major challenge for most of the present-day technologies and the technologies of the future is the compact and reliable design of electrical insulation systems for their electrical components,” said Ghassemi, who is the Steven O. Lane Junior Faculty Fellow and also a College of Engineering Faculty Fellow. “All electrical devices have insulators. Electrical insulators are materials with a high resistivity that allows them to prevent electric current from flowing where it is not wanted.”
Ghassemi’s five-year, $750,000 grant will support her work to address a gap in plasma modeling. Currently, there is not a complete model of all the discharges that can result in the breakdown of an insulation system. For nonthermal plasma, there have been studies that focus on only one mechanism or just the transition from one discharge mechanism to another. For thermal plasma, existing studies have focused only on the conditions following the occurrence of an electric arc or flashover. In both cases, a systematic study leading to a complete model comprising all discharge mechanisms is missing, Ghassemi said.
Ghassemi will develop a complete plasma model for both thermal and nonthermal plasmas using a hydrodynamic approach. The project aims to build the model sequentially, supported by experimental diagnostics covering a wide range of parameters.
“The model is expected to answer the question of whether or not there will be an electrical breakdown for a given complex geometry of electrodes and insulation systems under a given voltage waveform,” Ghassemi said. “The work has the potential to address industrial applications and is of great importance to higher voltage systems.”
The Department of Energy Early Career Research Program is designed to bolster the nation’s scientific workforce by providing support to exceptional researchers during their crucial early career years, when many scientists do their most formative work. The award program is highly competitive ― only 83 scientists from across the nation were selected in 2021.
Ghassemi’s award marks her third early career award as a faculty member at Virginia Tech. In 2020, she made history as only the second member in her department to receive the National Science Foundation CAREER Award and the Department of Defense Air Force Office of Scientific Research Young Investigator Research Program Award in the same year.